Device for excavating wells in the ground



June 14, 1955 A. P. JOURDAIN 2,710,739

DEVICE FOR EXCAVATING WELLS IN THE GROUND Filed June 7, 1950 2 Sheets-Sheet l June 14, 1955 A- P. JOURDAIN DEVICE FOR EXCAVATING WELLS IN THE GROUND 2 Sheets-Sheet 2 Filed June 7. 1-950 As! rs United States DEVICE FOR EXCAVATING WELLS IN THE GROUND Andr Paul Jourdain, Liege, Belgium, assignor to Compagnie Internationale des Pieux Arms Frankignoul, Societe Anonyme, Liege, Belgium Application June 7, 1950, Serial No. 166,738

Claims priority, application France June 10, 1949 7 Claims. (Cl. 255-4) types is practically limited to 500600 millimeters,

which corresponds to a working load of 100 to 150 tons.

Therefore, when it is desired to use those conven tional piles for supporting concentrated loads of e. g. 500 to 1000 tons or more, which are often encountered in foundations of high building and industrial premises, then it is necessary to resort to foundation footings of large dimensions, which involve high cost and space requirements which are sometimes not permissible.

It is for this reason that the necessity to form piles of large diameter, e. g. one metre or more, capable of bearing a Working load of 400 to 1000 tons, or even more, is being felt more and more. Since the sinking of such wells of such cross section cannot be efiected by forcing back the soil, it is necessary to provide for the removal of the earth.

The invention relates to a device which enables to carry out the boring of wells of large cross section in a convenient and expeditious way, with a relatively small expenditure of energy. The device essentially comprises an endless bucket chain mounted upon a support adapted to penetrate into the soil and carrying a driving unit for operating the bucket chain and carrying also a receptacle for collecting the earth extracted by the said buckets. The assembly is suspended from any lifting device and is capable of operating within a casing tube or even directly in the ground, should the nature of the latter allow so.

The invention has therefore for its object a selfcontained device which is linked with the surface of the ground merely by the suspension cable and the channels conveying the medium which is necessary for operating the driving unit. Thus, the assembly does not require any mechanical parts for the transmission of power from the surface, which parts are heavy and expensive, absorb a great deal of energy to no purpose, limit the amount of useful power that can be transmitted to the boring device, and slow up the work, since they are of necessity slow to actuate. Moreover, the aforesaid drawbacks become more marked as the diameter and the depth of the well increase, and they are effective in limiting both. The device of the invention eliminates all the aforesaid drawbacks and, more particularly, its working depth may be much bigger, as may also be its useful power.

Other features and advantages of the invention will appear from the disclosure of various embodiments given hereinafter by way of example with reference to the accompanying diagrammatical drawings, in which:

Fig. 1 is a vertical view, partly in cross section, of an arrangement for efiecting the sinking by means of the device according to the invention.

2,710,739 Patented June 14, 1955 vehicle which also carries a lifting device of any type,

e. g. a jib 4 carrying guide sheaves, such as 5, for a cable 6 operated by a winch 7 and having suspended thereon the excavator device. The latter comprises a shell or support 8 upon which there are mounted the chain Wheels 9, 10 around which the chain 11 carrying the buckets 12 is arranged to pass. The support 8 substantially comprises a cylindrical outer wall 13 and inner partitions, such as 14, forming a cage 15 for the chain 11 which projects downwardly at the lower end of the cage. The cavity 16 located between the outer wall 13 and the partitions 14 forms a receptacle which is closed by a bottom wall 17 and is intended to collect the earth extracted by the buckets and discharged by the latter across the opening 18. A cap 19 is secured to the cylinder 13 and provides for the suspension of the assembly on the hauling rope 6. The shell 8 further carries a driving unit operating one of the chain wheels. The driving unit may be of any suitable type, c. g. a compressed air or hydraulic motor, but will be preferably an electric motor, which need only be linked to the surface of the ground by a flexible power lead. A reduction gear will be interposed between the driving unit and the chain drive wheel.

In order to carry out a boring by means of the above device, the tube 1 is placed on the ground and the excavator assembly suspended on the cable 6 is lowered into the tube with a small play. When the excavator assembly is on the bottom of the tube, the driving unit is started, and the bucket chain, which projects from the base of the assembly, will excavate the soil and carry the earth upwards by means of the buckets 12. Upon tripping of the latter, the earth is discharged through the opening 18 into the receptacle .16. In fact, the earth each time drops onto the bottom of the preceding bucket and is thus directed towards the said opening. When the receptacle is full up, the excavator assembly is withdrawn from the tube 1 and the recep tacle emptied, whereupon the excavator assembly is im mediately lowered again into the tube in order to resume the boring. The above described steps are repeated until a well of the desired depth is formed, concreting of which may be effected subsequently in any suitable way, more particularly as the tube 1 is being withdrawn.

The action of the buckets is only effective over an eccentric portion of the cross section of the tube. As a rule, the earth in the remaining portion of the cross section will collapse progressively. Moreover, each time the excavator assembly will be raised, it will be practically lowered thereupon in a different angular position.

In the modification shown in Fig. 2, the support 8 only comprises the bottom wall 17 provided with an opening for the passage of the bucket chain therethrough, and a cap providing a closure for the cage 15 at the upper end thereof, the said bottom wall and the said cap being conneected by walls such as 14, which define the cage 15. The suspension cables 6 are attached to the cap 8. In the space 16 surrounding the cage 15 there is located a removable tank 20, suspended on the hauler rope 21 and having an opening in front of the opening 18. In this way, the excavator assembly may be left in the tube for the whole duration of the sinking action and all that will be necessary is to raise and to empty the tank 20 periodically while at the same time stopping the driving unit for the bucket chain.

In order to make the emptying easier, the space 16 of Fig. 1 and the tank 20 of Fig. 2 may be each provided with a removable bottom, or with openings in their top portion, in which case the emptying will be elfected by overturning. Moreover, if the tank 29 is omitted in Fig. 2, the emptying will take place automatically as soon as the excavator assembly comes out of the tube, since the receptacle 16 is not limited by an outer wall.

Figs. 4 to 6 illustrate a further modification with more structural details, which may moreover be used in the embodiments according to Figs. 1 and 2. In the said modification, the excavator assembly has a bottom wall 17 and a cage which is defined by side walls 14 and a cap 8. The latter carries an electric motor 22 and a reduction gear 23, e. g. comprising toothed wheels, interposed between the motor and the shaft 24 of the chain wheel 9, which shaft is operated through a transmission 25, e. g. a chain drive. The motor and the reduction gear are enclosed in a protector casing. The excavator assembly may be lowered into the tube 1 with small play, while a removable tank, such as (Fig. 2), may be located in the space 16. Or again, the assembly may be provided with a cylindrical wall such as 13 (Fig. 1).

In order to prevent the earth from dropping into the cage 15 when the buckets 12 are tripping, there may be provided an inclined discharge plate 26 abutting the lower edge of the opening 18.

In accordance with a further feature of the invention the removal of the earth will be favoured by the provision of break-up claws 27 arranged in suitably spaced relationship between the buckets. The shape of the claws may be made to suit the nature of the soil, and their number may be equal to the number of the buckets, as in the example shown, or it may be larger or smaller than that number.

The current is conveyed to the motor by flexible leads 28.

Moreover, means may be provided at the foot of the excavator assembly for breaking up the ground locally, such as through the medium of air blasts and/or liquid jets, for instance formed by a perforated peripherally arranged tube 2) to which the fluid is supplied through a pipe 30 connected to a flexible channel 31. Furthermore, on the shaft of the wheel 10 there may be mounted two tools, such as helical knives 32, adapted to act on the earth beyond the area of the cage 15, so as to scrape the earth towards this area.

It will be understood that the invention is by no means limited to the constructions described and illustrated, which are subject to numerous modifications without departing from the scope of the invention. As has been stated above, the excavator device may also be used to sink a well in the ground without employing a lining tube, if the nature of the soil permits so. In the latter instance it is useful to provide the assembly with a cylindrical jacket such as 13 (Fig. 1), which imparts a greater stiffness to the assembly, while forming a desirable guide along the wall of the excavated boring. When a lining tube is used, the latter may come down under its own weight as the excavating proceeds, or it may be driven a certain distance ahead of the excavator device. In all the examples illustrated, the excavator assembly shows a circular cross section, but it will be seen that it may show any other cross section, e. g. a square or a polygonal cross section.

What I claim is:

l. A self-contained device for sinking wells in the ground; said device comprising a support intended to be sunk in the ground and having a bottom wall substantially corresponding in shape to the cross-section of the Well to be sunk, an endless bucket chain mounted sub stantially vertically on said support and having its lower portion projecting through and below said bottom wall of the support for operating as an excavator in the ground below said bottom wall, a driving unit on said support for actuating said bucket chain, said bucket chain and driving unit occupying only a portion of the cross-section of the device defined by the shape of said bottom wall, receptacle defining means extending upwardly from said bottom wall and occupying the remainder of said cross- ..31 c. tn-c device left free by said bucket chain and driving unit, said receptacle defining means opening adjacent the upper portion of said bucket chain to collect the earth excavated by the buckets and discharged by the latter when the buckets are tripped, flexible means for conveying a medium for operating said driving unit, and means for freely suspending said support from a lift mechanism.

2. A device accorcing to claim 1; wherein said receptacle defining means includes the upper surface of said bottom wall around said bucket chain, and a cage extending upwardly from said bottom wall around said bucket chain and enclosing the latter, said cage having an opening in the upper portion thereof to provide the opening of said receptacle defining means adjacent the upper portion of the bucket chain, said receptacle defining means being completed by the wall surface of the sunk well above said bottom wall of the support.

3. A device according to claim 1; wherein said receptacle defining means includes the upper surface of said bottom wall, a cage extending upwardly from said bottom Wall around said bucket chain and enclosing the latter, said cage having an opening in the upper portion thereof to provide the opening of said receptacle defining means adjacent the upper portion of the bucket chain, and. a tubular wall extending upwardly from the periphery of said bottom wall so that the excavated earth is collected between said cage and tubular wall above said bottom wall.

4. A device according to claim 1; wherein said receptacle defining means includes a container having a side wall corresponding in cross-section to that of said remainder of the cross-section of the device left free by said bucket chain and driving unit, and a bottom formed to seat upon said bottom wall of the support.

5. A device according to claim 4; further comprising means for freely suspending said container from the lift device apart from said means suspending the support so that said container can be individually removed from the sunk Well for emptying the excavated earth collected therein.

6. A self-contained device for sinking wells in the ground; said device comprising a support intended to be sunk in the ground and having a bottom wall substantially corresponding in shape to the cross-section of the well to be sunk, said bottom wall. having at least one opening through a limited portion thereof, said support further including a cage extending upwardly from said bottom wall around said portion of the latter and having a cap at the upper end thereof, an endless bucket chain mounted substantially vertically in said cage and projecting downwardly through said opening in the bottom wall below the latter for operating as an excavator in the ground below said bottom wall, a driving unit for said bucket chain in said cap, means connected to said cap for freely suspending said support from a lift device, flexible means for conveying an operating medium to said driving unit in the cap, and a receptacle resting on said bottom wall of the support and having a cross-sectional shape corresponding to that of said bottom wall around said cage, said cage and receptacle having registering openings adjacent the upper portion of said bucket chain so that earth excavated by the buckets is discharged through said registered openings and collected in said receptacle when the buckets are tripped.

5 6 7. A device according to claim 6; wherein said recep- References Cited in the file of this patent tacle is removable from said support, and further com- UNITED STATES PATENTS prising means for freely suspending said receptacle from a lift device independent of said means for suspending 1 ghlpple the support so that the receptacle can be separately re- 5 65 Hyman moved from the sunk well for emptying the excavated armon June 9 earth collected therein. 2,187,845 Tatalovich Jan. 23, 1940 FOREIGN PATENTS 10 159,349 Germany Mar. 27, 1905 

